The semiconductor integrated circuit industry has experienced exponential growth. In the evolution of the semiconductor integrated circuit industry, functional density is generally increasing with reduced geometry size, and smaller and more complex circuits than the previous generation are produced. This scaling down process also increases the processing and manufacturing complexity of integrated circuits. For these advances to be realized, associated developments are required in the processing and manufacturing of the integrated circuits.
In the integrated circuits, capacitors are components used for data storage applications. Various capacitive structures are applied in the integrated circuits. These structures include metal-oxide-semiconductor (MOS) capacitors, p-n junction capacitors and metal-insulator-metal (MIM) capacitors. For some applications, the MIM capacitors provide certain advantages over MOS and p-n junction capacitors because the frequency characteristics of MOS and p-n junction capacitors are restricted as a result of depletion layers that form in the semiconductor electrodes. Also, the MIM capacitors formed in the metal interconnect layers reduces CMOS transistor process integration interactions or complications. Generally, the MIM capacitors exhibit improved frequency and temperature characteristics and a topology of a MIM capacitor simplifying planarization in the manufacturing processes.
With the aforementioned advantages, the MIM capacitors have been widely used in functional circuits such as mixed-signal circuits, analog circuits, radio frequency (RF) circuits, dynamic random access memories (DRAMs), embedded DRAMs and logic operation circuits. Therefore, there are constant needs for a method of forming a MIM capacitor to provide a MIM capacitor with improved reliability.